Continuous mixer



Oct. 22, 1940. -N, SQRENSEN 2,218,962V

coNTnmoUs MIXER Filed march 16, 1939' s sheets-sheet 1 :Fria-fl Gttorneg L. N. soRENsEN 2,218,962

CONTINUOUS MIXER Oct. 22, 1940.

3 Sheets-Sheet 2 Filed March 16. 1959 nventor ou/'s N Orense/7 Gttorneg Odi. 22, 1.940. Y N, SORENSVEN y 2,218,962

CONTINUOUS MIXER in section, showing the manner of mounting the Patented Oct. 22', 1940 I IH TUNITED PATENT oFFlCE4 My invention 'relates to the mixing offnely ground material, such as calcinedg'ypsur'n, cementv or the like with water and chemicals in a continuous operatic-n.1 f y! One object is to providev a means'whereby a dry powdered material is fed through'a vscrew conveyor preferably., althoughl other ffeeding means may be used, into afpipe from which. itis y fed through a rotating feeder vspout linto the A mixer where it is -joined with -a previously mixed solution of water and chemicals ina continuous-v mixing process.

Another object is to provide an a more simple and direct method for mixing the calcined gypsum or the like with the proper amount of water and chemicals to secure a more uniform product and eliminating the usual lumps and lack of uniformity in setting, `which `has heretofore been a principal defect with prior machines. f n

These and other objects will be noted from the following specification and its accompanying illustrations in which:

Fig. l is a top plan view of the machine. Fig. 2 is a side elevation of Fig. l.

Fig.3 is a section partly in elevation taken line 3-3 of Fig. 1.

Fig. 4 is an elevation of the rotorrwith the shell SWeepS.

- Fig. 5 is an enlarged section of one of the r0-v tary spouts discharging the mixture onto the bottom paper.

Fig. 6 is an enlarged section of the gypsum discharge feeder spout. Y y I Again referring to the illustrations:a screw conveyor I0 carries the dry material toa discharge pipe Il secured to the conveyor through which it passes downward into a rotating feeding spout I2 mounted rotatably within apbearing I3 secured to the said discharge pipe Il.

From the rotating feeding spout I2, the dry material is fed directly into the circular mixer shell or pan` I4 rearward of the water and chemical which is fed through the waterA line I5 and the chemical line. I6 into a mixing pipe IBa from which it is discharged into the mixer shell I4.

The feeder spout -I2 is rotated by means of a sprocket I'I on the periphery of the spout-I2 and a chain I8 driven by a sprocket I9 on the drive shaft which in turn is motivated through the usual gears 2I by a pulley 22 attached to a motor (not shown). l

A scraper 23 mounted on a bracket 23a on the apparatus withl top of the cross channel beam r24 extends down.-

ward from theslot IIa in the dischargepipefl I,I and within the rotating feeder spout I2 adjacent the inner wall thereof to keep the feeder spout A pluralityof mixing sweeps or arms 25 and 26l are mounted above a disk or rotor 21 within mounting blocks 28 secured to the flat faces of the hexagon post 3U, the sweeps being securedA therein by--set screws 3|, and the rotor 21 is heldl against the -Ibottomof the hexagon post 30 by? means of a nut 32 screwedv over the end of the `shaft 33. Pins 34 through the hexagon post and rotor prevent the turning of the rotor except as itv rotates with the assembly of sweeps and hexagon post. yThe mixing sweeps may be supported ad` jacent theperiphery of the rotor and secured thereto :by supporting posts although these arey notinecessary. v v

The sweeps 25 are preferably round rods 'while 'the single sweep 26 isv a square' scraper sweep,

and the round mixing sweeps 25 are radiated from the hexagon post each adjacent sweep above the previous'sweep, with the square scraper sweep 26 at the' top, and this sweepI keeps the top of the mixer shell I4 clean as it rotates around the `inner periphery of the shell adjacent the top edge.

'The channel 24 is mounted across the top" of the shell I4 and has an aperture 35 therethrough; and the rotating shaft 33 is shouldered at 33a',A the'jenlarged shouldered portion of the shaft extending upwardthrough the aperture 35 in the channel24`and the bearing 36, mounted within the said channel.'- y i They smaller portion of the shaft 33 belowy the shoulder 33a extends downwardly through the hexagonpost 3U and rotor 21. This shaft 33 preferably .isv rotated at approximately 300 to 500 R. PrM., by any suitable power geared or other# wise operatively connected to the shaft.

, The bottom plate 31 of the mixer is secured to the mixervshell I4 by any suitable means such as welding, bolting or the like, and a plurality of recesses or seats 38 are cut in the top surface of the bottom plate 31 adjacent the periphery of said bottom plate and below the rshell I4.

Gates 39 are'drawn out and pushed in at will withindthesemseats 38, and aperture 39athrough the center of the gates registering with the opening in jthe rotating discharge lspouts 40., said spouts'being mounted below vthe bottom plate 3l withinbearings 4I secured to the Abottom plate by bolts 42. l l

Scraper' bars 43 are mounted withinrthe rotati il al: l

rclear of the wet-mixture if and as it splashes`v 'IISI ing discharge spouts 40 and secured within a recess I4a in the shell I4 by bolts or screws 44.

Splash plates 45 are secured adjacent the bottom of the rotating discharge spouts 40 by bolts or screws 45a and revolve with the spout.

Splash plate scraper angles 46 are mounted on the bottom surface of the plate 31 bybolts 41, the flanged end of said scraper angles extending beneath the splash plates 45 to the edge of the inner wall of the discharge spouts 40.

Sprockets 48 around the periphery of the rotating discharge spouts 40 motivate the said spouts through a chain 49 over a sprocket 50 on the shaft 20, and this shaft revolves at approximately 30 to 60 R. P. M.

Scrapers I are secured to the disk rotor 21 by bolts 52 and are set on an angle to facilitate the sweeping action and scrape the bottom of the mixer pan. These Scrapers travel over the peripheral part of the bottom of the pan and serve to carry the mix around to the outlets.

, The mixer pan is supported on blocks or posts 53 at a suitable height above the table 54.

. In operation, the water and chemicals discharge into the mixing pipe I6a from their respective lines I5 and I6 and from the mixing pipe I6a into the mixer pan. The calcined gypsum feeds from the screw conveyor I0 through the discharge pipe II and the rotating feeding spout I2 into the mixer following the water and chem-` ical. The rotor disk 21 and sweeps 25 and 26 rotate at a comparatively high speed, whipping and mixing the wet and dry ingredients together as they revolve, and the gates 39 are pushed inwardly in the slots 38 and the wet mixture 56 is fed into the rotating discharge spouts 40 through the apertures 39a in the gates 39 and emerges in a plurality of streams on to anl equal number of bottom paper strips 55 passing over `the'table 54. The strips may be fed over the table by any suitable means, in a manner known in the art.

The Scrapers in the rotating spouts and beneath them, as well as those within the shell I4, keep the lumps from forming and produces a uniform product.

The paper 55 may be in l, 2 or 3 streams, depending upon what width product is being made as the machine is designed to take care of from one to three streams simultaneously. This paper is actually the face paper and is carried forward from the bottom rolls over a guide which is forward of the mixing machine and thence over the table 54 whereupon the wet mix or slurry discharges upon it and is carried forward beneath a master roller.

rPaper from the top rolls is carried over the mixer and driving mechanism and across a guide coming down vertically to the master roll.

The bottom sheets 55 have their edges folded so that the slurry does not leak out, this also makes a closed edge board. The top sheets go under the master roll on top of the slurry and forms the top of the board. The distance between the master roll and the table determine the thickness of the board and may be adjusted at will.

The board is then picked up by a carrier belt, the friction between the belt and board causing the board to move forward over a second belt to the knives where it is cut and carried forward over rollers to the transfer table. The weight of the boards on the carrier belts draw the strips or strings along.

AWhen'three strings of lath are made, three top and three bottom paper rolls are hung. The sheet from each bottom roll then passes under one of the rotating spouts of the mixture and carries one third of the wet mixture or slurri1 forward under the master roll where the top sheet is applied. The three strings of lath travel side by side on the carrier belt until they reach brass driven rolls which in turn carries them through the knife and delivers them to the` transfer.

Important features of novelty in the machine are:

1. The radial whipping sweeps of which there are six, these are so positioned in the mixing chamber that when set in motion will whip and lash the material to a perfect smoothness.

2. The splash plates 45 and Scrapers 43 are important because if these were not used the set stucco would build up and the machine would have to be stopped and the set stucco removed, otherwise it would tear the paper.

3. The rotating spouts through which the mixture is discharged and which prevent the material from clogging the discharge spouts.

4. The feature'of providing the mixer with three discharge rotating spouts.

I claim:

1. The combination with a mixing pan having a plurality of outlets in the bottom thereof, of a rotary spout carried in bearings at each outlet, a power shaft standing beside the pan and chain and sprocket gearing betweenV the shaft and said spouts, to rotate the latter.

2. In a mixer, a mixing pan, a rotating shaft associated therewith, said shaft having mounted thereon mixing sweeps comprising rods projecting outwardly therefrom and successively therearound and displaced successively one with respect to another` in the axial direction of the shaft, the displacement thereof in the axial direction of the shaft such that the sum of the vertical dimensions of theindividual sweeps is substantiallyV equal to the overall vertical dimension of the sweeps as mounted on the shaft.

3. In an article of manufacture comprising a machine for producing a stucco slurry, an horizontal circular substantially flat bottomed mixing pan, a vertical rotary shaft substantially centrally thereof, a rotary disc mounted on the lshaft for rotation thereby adjacent the bottom of the pan and spaced at its edge from the side wall of the pan to freely discharge the slurry from the disc into the peripheral portion of the pan by centrifugal force, outwardly projecting and substantially radially diverging, elongated sweeps carried by the shaft above the disc, the vertical projections of the sweeps in a vertical plane in substantial'edge to edge contact, a discharge port adjacent the periphery of the pan, and a feed port, the feed port spaced from the discharge port andr positioned inwardly therefrom with respectv to the side wall of the pan.

4. In an article of manufacture comprising a machine for producing a stucco slurry, an horizontal circular mixing pan, a vertical rotary shaft substantially centrally thereof, a rotary disc mounted on the lshaft for rotation thereby adjacent the bottom of the pan and spaced at its edge from the side wall of the pan to freely discharge the slurry from the disc rinto the peripheral portion of the pan by centrifugal force, outwardly projecting and substantially radially diverging, elongated sweeps carriedby the shaft above the disc, the sweeps comprising rod-like member successively arcuately displaced each with respect to the preceding and successively displaced along the axis of the shaft whereby the paths of the sweeps as they are rotated have the general effect of an ascending helix, the projections of said sweeps on a vertical plane being in substantial edge to edge contact, a discharge port adjacent the periphery of the pan, and a feed port, the feed port spaced from the discharge port and positioned inwardly therefrom with respect to the side wall of the pan.

.5. A substantially circular and horizontally positioned mixing pan, `discharge outlets arcuately spaced, one from another, adjacent the periphery of the mixing pan, below each said discharge outlet a dependent rotary cylinder through which the discharge outlet is adapted to discharge, bearings rotatably supporting a rotary dischargev cylinder in dependent relation with respect to each of such discharge outlets, and a stationary scraper member for each rotary discharge cylinder,

each of such stationary scraper membersmounted exteriorly of its respective discharge cylinder and having a portion thereof extending into and positioned adjacent the interior periphery of its respective rotary discharge cylinder.

6. In a mixer adapted for theproduction of a hardening slurry, a mixing pan, the mixing pan having peripherally thereof a discharge spout leading therefrom and comprising a rotary cylinder, bearings rotatably supporting the cylinder and means for rotating the cylinder, each such rotaryy cylinder carrying at its outer end a flangelike outwardly projecting splash plate rotatable therewith.

7. In combination in a mixer adapted for the mixing and discharge therefrom of a hardening slurry, a mixing pan, a discharge spout therefor,

a ange-like splash plate carried by the terminal portion of the discharge spout, and stationary scraper members, one of the scraper members positioned closely adjacent the interior peripheral surface of the discharge spout, the other scraper member mounted closelyadjacent the lower face of the splash plate, and meansy mounting the discharge spout and splash plate with'respect to the Scrapers whereby the scraper members respectively may scrape from the interior of the discharge spout and from the lower face of the splash plate slurry tending to adhere thereto.

8. In combination in a mixer adapted for receiving, mixing, and discharging therefrom ingredients comprising when mixed a hardening slurry, a mixing pan, a rotating mixing member therein, feed and discharge spouts, each suchl ylindrically formed members, stationary scraper means mounted exteriorly of but extending into the interior of each ofsaid cylindrically formed members and positioned adjacent `the respective interior peripheral surfaces thereof, and means for rotating each of said cylindrically formed members whereby hardening material tending to collect on the interior surfaces thereof will be detached by the scraping action of the respective scraper means.

9. In a mixer adapted for the production of a hardening slurry, a mixing pan, the mixing pan having adjacent the periphery thereof a discharge port, a discharge spout leading from said discharge port kand vcomprising a cylinder rotatable relative to the mixingv pan, bearings rotatably supporting the cylinder in receiving relation adjacent the discharge port and means for rotating the cylinder.

k10. In the combination of a mixing pan with a feeding supply-spouttherefor mounted thereover for discharge thereinto, the feeder spout comprising a stationary portion and a rotary cylindrical portion, the rotary cylindrical portion interposed therein immediately adjacent the discharge thereof into the mixing pan, bearings rotatably supporting the rotary portion of the feed spout, a stationary scraper member mounted exteriorly of the rotary feed spout and extending thereinto closely adjacent the interior peripheral surface thereof and meansto rotate the rotatably mounted portion of the feed spout.

11. In combination in a mixer adapted for mixing therein and discharging therefrom a hardening slurry, a mixing pan, a discharge port in a wall of the mixing pan, a discharge spout mount- LOUIS N. SORENSEN. 

